'commit'

TangDou/AcWing/LIS/1012_2.cpp

@@ -0,0 +1,29 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+typedef pair<int, int> PII;
+#define x first
+#define y second
+
+const int N = 5010;
+PII a[N];     // 南岸和北岸的一对友好城市的坐标
+int f[N], fl; // 数组模拟栈
+int n;        // n组友好城市
+int res;
+
+int main() {
+    cin >> n;
+    for (int i = 1; i <= n; i++) cin >> a[i].x >> a[i].y;
+    sort(a + 1, a + 1 + n);
+
+    f[++fl] = a[1].y;
+    for (int i = 2; i <= n; i++) {
+        if (a[i].y > f[fl])
+            f[++fl] = a[i].y;
+        else
+            *lower_bound(f + 1, f + 1 + fl, a[i].y) = a[i].y;
+    }
+
+    printf("%d\n", fl);
+    return 0;
+}